From ab5b1796147b9d4e2513fd9e514891392e4308c3 Mon Sep 17 00:00:00 2001 From: Nils Wallménius Date: Tue, 28 Mar 2006 12:18:51 +0000 Subject: *** empty log message *** git-svn-id: svn://svn.rockbox.org/rockbox/trunk@9308 a1c6a512-1295-4272-9138-f99709370657 --- manual/plugins/alpinecdc.tex | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100755 manual/plugins/alpinecdc.tex (limited to 'manual/plugins/alpinecdc.tex') diff --git a/manual/plugins/alpinecdc.tex b/manual/plugins/alpinecdc.tex new file mode 100755 index 0000000000..f24ee80452 --- /dev/null +++ b/manual/plugins/alpinecdc.tex @@ -0,0 +1,39 @@ +\subsection{Alpine CD changer emulator} +This plugin emulates an Alpine CD changer. It allows to plug the Archos to a +compatible head unit and control the playback from there, too. Currently +implemented is track change, shuffle, seek, but no disk change. The plugin is a +TSR, meaning it silently operates in the background once started. It will keep +doing so until a new plugin is started. +Alpine also did M-Bus as OEM for other brands (Honda, Acura, Volvo, BMW, etc.) +Nowadays Alpine uses a different protocol, called Ai-Net, not supported by this +plugin. (As well as all other protocols, please do not ask for such!) + +\subsubsection{The cable} +Hookup to Archos works by connecting the headphone output including the remote +pin (you need a 4-ring 3.5 mm plug for that) to the changer jack of the radio. +M-Bus radios have a DIN-style circular jack with 8 pins (7 in a $\sim$ 270 degree +circle, one in the center). A standard 5-pin DIN plug is OK for this, since we +don't use the other (power) pins. + +As OEM, they shuffled the pins around a bit, better check first if it's not +genuine Alpine. The bus pin is pulled high to 12 volts with a $\sim$ 2kOhm resistor, +pulses driven low. Because it's open collector, this is not harmful to the +Archos.\\ +ASCII art of the 4-pin headphone plug: +\begin{verbatim} +/ \ +\_/ left -> Alpine pin 5 +|_| right -> Alpine pin 4 +|_| remote -> Alpine pin 1 +|_| ground -> Alpine pin 2 + 3 +\end{verbatim} + +The remote pin can be programmed bidirectional, that's the reason this works. +Very luckily the M-Bus uses a single wire communication and the two radios I +tried are happy with the 3.3 Volt level the Arcos can deliver. So the +connection is a simple cable! For all protocols requiring more lines, an +external controller would be necessary. + +\textbf{Note:} Archos FMs don't have the remote pin internally connected, but +one unit that was opened was internally prepared for it, a matter of closing a +bridge. -- cgit v1.2.3